This invention relates to portable power distribution systems, and is specifically concerned with a power distribution system for use under low-light emergency conditions, such as an accidental fire in a building.
Emergency power distribution systems for use by firemen are known in the prior art. Such systems generally include a power cable that is connected to a power source (which may be the portable generator aboard a fire fighting vehicle) at one end, and to a plurality of power distribution cables at its other end. Power outlet blocks having receptacles may be connected at the ends of each of the power distribution cables. These power outlet blocks are generally rectangular in shape, and have housings formed from stamped metal to protect the receptacles which they house. The power distribution cable and outlet blocks are all interconnected by male and female connectors of blade-type connector assemblies of the type which may be inserted into standard 120 volt wall sockets. The conductive elements used in the male connectors typically include a pair of flat copper strips which are insertable into rectangular slots located in the female connectors. A ground-wire prong may also be included in each of the connector assemblies to minimize the possibilities of electrical shock and short-circuiting.
Such portable power distributing systems are often an indispensable component of the tools used by firemen in at least two respects. First, they are used to set up an emergency array of floodlights around and within the building being quenched. Such floodlights are often necessary as the smoke generated by fires creates an obscuring fog in the vicinity of the burning building that makes it very difficult for the firemen to manipulate water hoses into the proper positions to effectively quench the fire. Even in a situation where there is little or no smoke, many fires occur at night, and so an emergency array of floodlights is still necessary. Secondly, such power distribution systems provide electrical power for the smoke blowers used by modern fire departments to help dissipate the obscuring haze created by the smoke of a building fire.
While such prior art power distribution systems are generally capable of providing the electrical power needed by fire fighters under many conditions, the applicant has observed a number of shortcomings associated with the components used in such systems. For example, neither the housings of the outlet blocks or of the connector assemblies are capable of withstanding the crushing forces that the wheels of a fire fighting or other type of emergency vehicle can apply. This deficiency, coupled with the fact that the power distribution cables, connector assemblies and power outlet blocks associated with such systems are difficult to see under nighttime or smoky conditions, can sometimes result in the crushing and hence inoperability of on or more of the power outlet blocks or connector assemblies of the system. Such inoperability in turn results in the inability of the system to provide the power needed for the floodlights and smoke blowers at a particular location. The applicant has further observed that the power outlet blocks and connector assemblies have no provision for effecting a water-tight seal between the prongs and recesses of the male and female connectors. This is a serious shortcoming, as the outlet blocks and connector assemblies frequently become wet either by being inadvertently sprayed by fire hoses, or being immerse in the water that often collects in pools around the site of a fire as a result of the water sprayed from fire hoses. The resulting short-circuiting not only can result in a serious power outage, but can also be life-threatening to the fire fighters handling the power distribution system. The applicant has further observed that it is difficult for firemen to properly align and insert the blades and slots of the male and female connectors used in such prior art power distribution assemblies due to both the low ambient light conditions, and the tearing that the often toxic smoke often induces in the eyes of firemen. Finally, the applicant has observed that the male and female connectors of the electrical connector assemblies are prone to accidental disengagements hen a relatively small amount of tensile force is inadvertently applied to them, which may occur when a cable is run over by a fire fighting or emergency vehicle, or dragged to a new location, or even tripped over by a fire fighter or fleeing inhabitant of the burning building.
Clearly, there is a need for an emergency power distribution system having power outlet blocks and connector assemblies which are both crush-proof and waterproof. It would be desirable if both the power outlet blocks and the connector assemblies resisted the collection of water under wet conditions so that no power outages or life-threatening short-circuiting occurred during the assembly, use or disassembly of the system. Finally, it would be desirable if the conductive members encased in the connector assembles could be easily and quickly engaged, but yet were not easily disengagable, so that the electrical connection between such connector assemblies stayed in tact when an inadvertent tensile force was applied hereto.